Cupping, Rusty, Pale Leaf Edged Coco Plant?

[Seb]

I have five plants (different cultivars) in coco. They are all happy except this one. Any ideas on what she's unhappy about?
I've tried giving her some extra epsom salt (Mg). That seems to have helped but I'm not sure.
I'm feeding around 1.2ec until runoff. Any suggestions?

Given that the other plants are happy I hope it's this particular plant rather than my approach in general.

Cheers



This is the rest of the tent. I used bad soil and pots that were too large. I think that's why the girls in soil are not impressed. I repotted them yesterday which seems to have helped.

 

[steamroller]

That is Mg and a little Ca deficiency IMO.
Now you are in coco I think the pH of your water is important so you should check it at the source and runoff.
The pH could be locking the Mg out.
Applying the Mg foliar/spray will help correct quicker.
Keep your eye on new growth. The old will not repair itself.
This on Mg;

Cannabis Magnesium Deficiency Pics & Chart by DRCANNABIS.IO

In A Cannabis Magnesium Deficiency Leaves Will Show Symptoms Beginning With Older, Lower Leaves, Which Will Show A Yellowing Between Their Green Veins.

drcannabis.io

Taken from; https://drcannabis.io/symptoms

I'll add I have never grown in coco.
@Aqua Man will know best IMO.

 

[Observer]

Possibly, just a heavier feeder.

If everything else is within range and it's only this strain showing.

 

[Aqua Man]

May wanna lower the light intensity also. Looks like some bleaching is happening

 

[Seb]

Thanks everybody.

I'll apply Epsom foliar spray tonight. I'll double check the light intensity. I think it's on 400ppfd. Afaik the light amplifies most issues a plant may have. I thought I was on the low end of reasonable ppfd so the plants in soil can recover.

 

[Aqua Man]

Thanks everybody.

I'll apply Epsom foliar spray tonight. I'll double check the light intensity. I think it's on 400ppfd. Afaik the light amplifies most issues a plant may have. I thought I was on the low end of reasonable ppfd so the plants in soil can recover.

Yeah they are still small so 250-300 is prob what they would like… 400-600 is usually a late veg number

 

[Seb]

Yeah they are still small so 250-300 is prob what they would like… 400-600 is usually a late veg number

Thanks Aqua Man. I appreciate you checking in on my grow.

PPFD was around 480. I've lowered it to 250-300 and moved the struggling plant to the edge so it gets the low end of that PPFD range.

I checked my runoff for the first time and it's way out of control. I had a ph of almost 8 and 2.5ec. I've lowered the feed to 0.9ec (down from 1.2). I would guess the pots are fairly large for what the plants currently are so more water is evaporating than being consumed by the plants.

 

[Aqua Man]

Hiw much are you watering at a time and how often?

 

[Seb]

I've been watering 1-2 / day until runoff, manually until now. I can't tell you exactly how much in terms of volume. I'd guess around 400ml / plant. I checked the weight of the pots, made sure they don't get dry and watered until runoff.

I have my pump set up now. I'll measure the amount of feed and runoff. I've read @Aqua Man 's post on watering coco. That's what I'll use as my guide.

 

[Seb]

I just fed them 1L for all 5 plants combined and got about 200ml runoff. It has been 5-6 hours since the last watering. Does that mean watering once a day is fine for now? That would be my plan.

 

[Aqua Man]

I just fed them 1L for all 5 plants combined and got about 200ml runoff. It has been 5-6 hours since the last watering. Does that mean watering once a day is fine for now? That would be my plan.

Id go once at lights on and once in the middle of lights on. Measure the runoff of the first feed to see when you need to add a 3rd

 

[Max]

i think you are going to have to reset the media by flushing quite abit of nutes through to get your ppm of runof down where you want it. Those big ass pots at there young age don’t help either.I run like 3 litres through pots close to that size when plants are 6 weeks old with heaps of runoff just to keep on top of buildup and up to 4 litres into flower..

 

[Aqua Man]

i think you are going to have to reset the media by flushing quite abit of nutes through to get your ppm of runof down where you want it. Those big ass pots at there young age don’t help either.I run like 3 litres through pots close to that size when plants are 6 weeks old with heaps of runoff just to keep on top of buildup and up to 4 litres into flower..

Yeah that flew over my head. Numbers our should be close to numbers in… around 20% or so

 

[Seb]

Thanks for the catch, Mad Max. I'll whip up some mild nutrient solution and give them a good flush. Next time I'll go for smaller pots. I'm also considering options for getting the space heated up. It's around 72f now that the lights are on lower PPFD. I thought the room would heat up over time but it's too big for the light to make a dent at the current power settings. I'd love to put in a dry wall which would give me an awesome grow space. That's the next project.

 

[Seb]

I sent around 10-15L through the system. Runoff is down to 1.5ec, ph still around 7. I'll keep an eye on it and see what I can do about the temps until the dry wall is up...

 

[Max]

You have to run 3 times that to get it under control I reckon bud....try 250ppm and when it’s down to say 400 runoff give them 350-400 nxt watering..
if you don’t do it it will lead to problems when you get into flower you will b chasing your tail to get it under control..

i use 4.5 litre pots up to week 5 and they have extra chunky perlite added to 70/30 buffered bag.I can get away with one feed a day in my environment.it could b better .the 4.5 litr pots are given 1 litre ea feed .when first up potted at day 18 or so they were getting about 750ml…I have a lot of runoff..it’s wasteful but it works..